Fair Value Measurements - Schedule of Fair Value Measurement on Recurring Basis (Details) - USD ($)	Jun. 30, 2020	Jun. 30, 2019
Investment in marketable securities	$ 6,178,000	$ 9,696,000
Level 1 [Member]
Investment in marketable securities	6,178,000	9,696,000
Level 1 [Member] | REITs and Real Estate Companies [Member]
Investment in marketable securities	2,365,000	3,069,000
Level 1 [Member] | Basic Material [Member]
Investment in marketable securities	1,209,000
Level 1 [Member] | Energy [Member]
Investment in marketable securities	767,000	950,000
Level 1 [Member] | Industrials [Member]
Investment in marketable securities	484,000
Level 1 [Member] | Corporate Bonds [Member]
Investment in marketable securities	417,000	1,420,000
Level 1 [Member] | Other [Member]
Investment in marketable securities	$ 936,000	1,858,000
Level 1 [Member] | Consumer Cyclical [Member]
Investment in marketable securities		1,448,000
Level 1 [Member] | Financial Services [Member]
Investment in marketable securities		$ 951,000